Ignition timer



Patented Aug. 23, 1927.

entren STATES WILLIAM n. nnowuyor PHILADELPIII. PENNSYLVANIA.

IGNITION 'Jini/IFR.

Application filed October 29, 1923. Serial 1.10. 671,431.

My invention relates to contact devices y and more especially to lsuch devices as are applicable to automobile ignition systems.

@ne `object of vmy invention is to provide a contact maker and interruptertor ignition systems, wherein substantially uniform Aprimary current is maintained for all running speeds. y

Another object ot my invention is to .provide a device of the class speciied `which is characterized by the avoidance Aof pittingand uneven wear ot the interrupter conk tact points.

.A further object of my invention is to pro- Vide a Contact maker and interrupter of compact and rugged design, suitable for quantity production methods of manufacture and comprising` parts which 'maybe easily made and assembled at a minimum expenditure of time and of money. y

It is characteristic ot the prior-art timer ldevices that very heavy currents were required 'lor slow running speeds in order that there be sufficient currents pass through the device tor the higher speeds. The excessive currents employed resulted inzthe pitting ot the contact points. and lother difficulties l-:novvn to those skilled in the art. Y

Accordingto my invention, I provide Va contact maker and interrupter which avoids the above mentioned undesirable characteristics by providing` mechanism for increasing and decreasing the duration of the contact period of the spark Vpoints in accordance with the variations in speed of the motor. Sparking is further decreased in, the device embodying` my invention by so designing the contact maker and interrupter as to cause the contact points tohave a substantially straight line make-and-break motion. The contact vmaker and interrupter for carrying the foregoing' desired vresult into effect comprises a pair ot co`acting relatively movable contact points having; pivotal sup ports, one of the points beine` movable in a transverse direction to that afforded by the pivotal supports; a revolubler shafthaving a cam thereon operable `to etlect the en- `a'ageinent ot said movablecontactpoints or the transverse movement of one of said points depending,` upon the direction of rotation thereot; and a cam plate for supporting said contact members, whereby the latter may be moved angularly as Well as radially with respect to said @am t WIIY' the time and the `duration ot the sparking: period. i lfVith these and other objects and applica tions iinmind, my invention further consists in the details ot' construction and operation and arrangement, .hereinafter set torthnand claimed and illustrated in the accompanying drawings` wherein y Fig. l is a top-plan view of one form of embodiment of my` invention; and Fie'. 2 isy a transverse sectional view taken on the line HMH of 1,.

In the illustrated form of embodiment oit my invention shownin the drawing, a rotarv timing' shaftl is revolubly mounted in a bea-ringF member 2 whichlis rigidly secured in a perforation 3 formed in a supportinar plate 4. One end ot' the shaft 1 projects beyond the bearing memberL 2 to providey a mountingtor a collar 5 which is Provided with a plurality 0I' cam projections ,6. Each cam yprojection 6 comprises a sloping portion 7 y and an abrupt portion 8, for reasons as will appear moretully hereinafter.

A pair of contact points or members 9 and 11'are mounted on the fend portions of lv pair of switch or lever arms ,12 and 13, respectively, which are pivotally mounted about a common pivot pin 1li. The pivot pin 14 is supported on a movable plate 15 which will -be explained more fully hereinafter.r

The contact point 9, in contra-distinction to the contact point 11, is insulatingly supported on the end portion of the arm 12 by 4means of a bushing 16 of fiber or other insulating material. The contact member 9 may be connected to a bindingpost 17, which 1s insulating'ly supported on the plate 15, by mea-ns of a spring` conductor 18, the i latter also serving to provide a resilient .mounting for the end portion of the lever arm 12.` The binding post 17 may be connected to' alterminal lug; 19, which is insulatingly supported on the plate 15, and

which'` constitutes one external terminal connectiontor the interrupter. Inasmuch as the remaining contact member 11 is not insulated from the supporting structure, the remaining external terminal `connection may be made atany convenient un-insulated portion thereof.` y

The outer end, of the lever arm 13 is so bent as to provide a projecting portion 2O which is adapted to be engaged by the cam projections G as the shaft 1 revolves, whereby the contact member 11 may be intermittently actuated into engagement with the contact member 9. The inner end of the arm 13 has a portion 21 partially curved around the pivot pin 14 and terminating in a latterly extending portion 22. A spring 23 has one end thereof secured to the projection 22 of the arm 13 and it has the other end vthereof secured to a post 24e, which is mounted on the supporting plate 15, whereby a resilient force may be exerted on the arm 13 tending to maintain the relatively movable contact points 9 and 11 in spaced relation. The mounting for the arm 13 about the pivot pin 14, just described, thereby provides for transverse or longitudinal as well as pivotal movement, whereby the Contact member 11 may be moved bodily away from the contact member' 9 and whereby the contact member 9 may be moved into and out of engagement with the contact member 11 in a substantially straight line direction.

The lever arm 13 is guided during its bodily movement by a guide member 25 having a recess 26 therein which is adapted to slidably receive the lever larm 13. Further guiding of the lever arm 13 may be effected by providing` the other lever arm 12 with upper and lower flange portions27 and 23 which are perfo vated to receive the pivot pin 1li and which are spaced apart to such extent as to engage the opposite edges of the bodily movable lever arm 13, all as shown in the drawing.

The position of the contact member 9 with respect to the contact member 11 may be varied by means of a circular member which is mounted for turning about the post 24 and which is provided with a projecting portion 30 of hook-like form adapted to engage the side of the lever arm 12. A portion of the circumference of the circular member 29 is provided with a series of teeth 31 which mesh with a similar series of teeth 32 also formed in the circumference of a circular member' 33 of considerably reduced diameter, the latter' member 33 being mounted for turning about a screw member 3-1 secured to the plate 15. The members 29 and 33 thus provide a micrometer adjustment for variations in the position of the contact point 9 with respect to the contact point 11.

lVhen the shaft 1 is rotated in the direction of the arrow shown in the drawing, the contacts 9 and 11 are held in spaced relation by the force of the spring 23 on the projecting portion 22 of the arm 13 during the time interval between the successive engagement of the cam projections 6 with the projecting portion 20 of the lever arm 13. its the sloping portion T of the cam projection 6 is actuated into engagement with the 20, whereupon the contacts 11 and 9 are suddenly separated under the force of the spring 23. The foregoing engagement and disengagement of the contacts 9 and 11 occurs a number of times for each revolution of the shaft 1 depending upon the number of cam projections 6.

Then the shaft 1 is revolved in the reverse direction, as obtains when the driving motor (not shown) back-tires, the abrupt portion 3 of the cam projection 6 is actuated into engagement with the projecting portion 2O of the lever arm 13, causing a bodily movement of the same between the guide plates 27 and 23 of the lever arm 12 until the edge of the abrupt portion 3 of the cam projection G passes over the end of the lever arm projection 29 to release the same. The lever arm 13 is then moved back into its original position by the force ol the spring 23.

As hereinbefore pointed out, l have found that the undesirable operating characteristi e of sparking and pitting of the contact points, which is caused, among other things, by the heavy currents which must be carried at low speeds in order to provide suiiicient currents for the higher speeds, may be avoided by providing a. construction wherein the relative spacing of the contact members 9 and 11 may be varied in accordance with the speed of the motor (not shown). 'llo this end, l have mounted the contact members 9 and 11 and the supporting apparatus iniinediately associated therewith upon the plate 15 which embraces an eccentric bushing formed on the bearing member Movement of the plate 15, which may be caused by a projecting handle portion 3 causes the projecting portion 2O of the arm 13 to be moved toward o1' away from the several cam projections 6, thereby increasing or decreasing the duration of the Contact period, i. e., the time interval during which the contact members 9 and 11 are in engagement. The angular movement of the lever arm projection 20, obtaining when the plate 15 is moved, also effects a variation in the time at which the cam projections G and thc lever arm projection 20 are actuated into engagement and hence the time of contact of the relatively movable contact members 9 and 11.

Vhile I have shown but one enibodiment of my invention, for the purpose of describing the same and illustrating its principles of construction and operation, it is apparent that various changes and modifications may be made therein without departing from the spirit and scope of my invention. I desire, therefore, that only such limitations shall be made thereon, as are indicated inthe appended claims or as are Vdemanded by the prior art.

I claim:

l. In combination, a pair of switch arms having a common pivotal mounting and provided with co-acting contact members,'means for causing one of said contact members to engage periodically the other, and `a resilient abutment for said last-mentioned member, said common pivotal mounting permitting one of said switch arms to `have a pivotal aswell as a bodily movement in response to said means independently'of the other.

2. In combination, an arm, a co-acting arm having differential movements, means providing a common pivotal mounting for said arms, and revoluble means operable to give said co-acting arm one or the other of its movements depending upon the direction of rotation of said second-mentioned means, one of said movements being into engagement with said first-mentioned arm, the other of said movements occurring independently of said last-mentioned arm. n

. 3. In combination, a pair of co-acting relatively movable contact members having common pivotal supports, said members having substantially a straight-line movement, one of said members being movable longitudinally of the other, means for causing said straight-line movement or said longitudinal movement and a cam for supporting said contact members, whereby said contact members may be moved toward and away f from said means.

4. In combination, a pair of (Jo-axially mounted arms carrying cooperating contact members, and means for resiliently holding said contact members in spaced relation, one of said arms being also movable substantially longitudinally of the other, said means serving to resist said longitudinal movement, one of said arms constituting a guide for the other during said longitudinal movement. f

5.`In combination, a pair of arms having a common pivotal support and provided with cooperating cont-act members, resilient means for opposing` motion of one of said arms, the other of said arms being movable bodily from said support independently of said first-mentioned arms, resilientlmeans for resisting said last-mentioned motion and for holding the contact member carried by said last-mentioned arm out of engagement with the other contact member, and a shaft having a cam provided with abrupt and sloping surfaces, said sloping surfaces b-eing movable, for one direction of rotation of said shaft, into engagement With said bodily-movable arm, to cause yengagement of said contact members, said abrupt surface 6i The combination 'with a pair 'of armsl having a commonpivotal support and provided witli cooperating cbn'tact members, resilient means for opposing motion of one of said arms, the other of said arms being movable bodily from said support,resilient means for resisting said last-mentioned motion and for holding said contact members out of engagement, a shaft having a cam provided with abrupt and sloping portions, the latter portion befng operative,'for one direction lof rotation of said shaft, to effect the engagement of said contact members,"the former portion being operative, for a reverse direction of rotation of the shaft, to bodly move said bodily-movable member until said abrupt portion has cleared the same, and a cam plate for so supporting said arms that the same are movable toward and away from said first-mentioned cam.

7. In a Contact device, a pivot pin, an arm having a contact member at one end and provided with perforated spaced flange portions at the other end, said perfor-ations being adapted to receive said pivot pin, and a second arm having a Contact member at one end and provided with a bent-back portion at the other end, whereby said second arm may have a pivotal as well as a bodily movement, said spaced flange portions constituting guides for said second arm.

8. In a contact device, apivot pin, an arm having a Contact member at one end and provided with perforated spaced flange portions at the other vend, said perforations being adapted to receive said pivot pn, a second arm having a contact member at one end and provided with a bent-back portion at the other end, whereby said second arm may have a pivotal as well as a bodily movement, said spaced flange portions constituting guides for said second arm, and a movable stop member for said first-mentioned arm, having a micrometer adjustment.

9. In a contact device, a pivot/pin, an arm having a contact member at one end and provided with perforated spaced flange por-- tions at the other end, said perforations being adapted to receive said pivot pin, means for resiliently holding said arm in a desired position, a movable stop member for said arm having a micrometer adjustment, a second arm having a contact member at one end and provided with a bent-back portion at the other end, and resilientmeans for exerting a force on th@ free end of said bent-back portion, whereby pivotal as well as bodily movement of said second arm is ill? resiliently opposed, said spaced flange portions constituting,r guides for said Second arm.

l0. In combination, a pair of switch arms adapted to carry contacts, and means affording' a common pivotal mounting for Said arms, one of said arms being movable transversely of the other and guided thereby.

l1. A switch arm havingl a pair of spaced iangee adapted to receive therebetween a Second switch arm7 said flanges being' also adapted to engage a pin affording said arms a common pivotal mounting'.

l2. A switch arm having a pair ol' spaced flanges adapted to receive therebetween a Second switch arm, at least one of Said lianges being` also adapted to engage means affording Said arms a common pivotal mounting, and a movable stop member for said arm havingl a micrometer adjustment.

13. A timer comprising a switch arm provided with spaced flanges, a second arm, and

means affording a common pivotal mounting;r for said arms but permitting` an independent bodily movement of one arm relative to the other.

'14. In combination7 a pair olf sivitch arme, of which one is provided with at least one flange adapted to support the other1 and means affording a common pivotal mounting for said arms7 whereby one ot said arme may be movable bodily relative to the other arm, Said liange constituting a guide 'for said bodily movable arm.

l5, ln a timer, the combination with a switch arm provided with spaced llaiigzljeaa of a second switch arm` and a pivot pin at fording` sad ewitch arme a. common pivotal mounting', one of eaid arms being so 'formed as to movable bodily awa)7 from said pivot pin, said llangeil switch arm servingl as a guide duringl said bodily movement.

V'ILLIAM H. BROVN. 

